Display screen or portion thereof with an animated graphical user interface



FIG. 1 is a front view of a first image in a sequence for a display screen or portion thereof with an animated graphical user interface showing our new design;

FIG. 2 is a front view of a second image thereof;

FIG. 3 is a front view of a third image thereof;

FIG. 4 is a front view of a fourth image thereof; and,

FIG. 5 is a front view of a fifth image thereof.

The broken lines in FIGS. 1-5 of the display screen or portion thereof with an animated graphical user interface are for the purpose of illustrating environment, and form no part of the claimed design.

The appearance of the transitional image sequentially transitions between images shown in FIGS. 1 through 5. The process or period in which one image transitions to another image forms no part of the claimed design. 

CLAIM The ornamental design for a display screen or portion thereof with an animated graphical user interface, as shown and described. 